Five students reported the amount of time they spent studying

Video Transcript

We have a data set here: 5 students reporting the amount of time they studied for a test a night before the test for part a we want to work out the mean. So, to get the mean you take each data point which we'll call x, i, which will be x, 1 x, 2. So you add all of them up. So you get the sum and then you divide by the total number of pieces of data. So here we have 45 plus 50 plus 60 plus 65 plus 80 point we're dividing all of this by 5, and that will give us the mean, so the mean what we'll call x bar here is equal to 60 point. Next, we want to find the standard deviation, so the standard deviation is the square root of the variance and his formulae. Variance you take each piece of data again this time you take away the mean so you're, finding the difference between the 2. You square it and the reason you do. That is because, if you have some below the mine and some above you don't want them to cancel each other out, you want all of your values to be positive, so you square them, and then you add up to you sum the squared differences and you divide By the number of pieces of data- and that's the variance, so the variance is going to be- we have 45 minus 60 square adds 50 minus 60 square 60. Minus 60 square have the others over here: 65 minus 60, squared and 80 minus 60 squared and all of that divided by 5. That gives us the variants which are put in red. So we don't mistake it for the answer is the variance here is 150 point. The average squared difference between a piece of data and mamine, and now all we have to do to turn it into a standard deviation, is square rooted square roots and from 50. Of course we want to be positive answer here, not the negative, so it's 12.25 to 2 decimal places.

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Five students reported the amount of time (in minutes) they spent studying for an AP Statistics test the night before the test. The mean of the reported times is 45 minutes and the standard deviation is 10 minutes.
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Step-by-step explanations Get personalized help from subject matter experts We break it down for you Well ge esc < > Q () @ 2. Five students reported the amount of time (in minutes) they spent studying for an AP Statistics test the night before the test. The mean of the reported times is 45 minutes and the standard deviation is 10 minutes. (a) Interpret the standard deviation in context. M command (b) A 6th student reported that they studied for 50 minutes. How would the addition of this student to the com data set affect the value of the mean and the standard deviation? Explain your answers. 2020 BFW Publishers Inc. Stares labor, ( plated Version of The Practice of Statistics W/c.

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Five students reported the amount of time (in minutes) they spent studying for an AP Statistics test the night before the test. The mean of the reported times is 45 minutes and the standard deviation is 10 minutes.

Answer :

Answer:

a) mean = 60 min
b) standard deviation = 13.7 min

Step-by-step explanation:

Question

Five students reported the amount of time (in minutes) they spent studying for an AP Statistics test the night be the test.

Here are the results: 45 50 60 65 80
a) Calculate the mean of study times using the formula. Show your work!
b) Calculate the standard deviation of study time using the table and formula. Show your work!